This proposal concerns the study of human motor control through measurement of free arm movements. A commercially available movement monitoring system, the Selspot System produced by Selcom Corporation, provides for the first time the capability for fast accurate measurements. The advantage of accurate measurements of free arm movements is the richness of the set of trajectories that can be measured, revealing corresponding insights into motor control issues such as joint coordination, spacetime tradeoffs in movement computation, and adaptation of learned movements to new situations. The context for the experimentation is developed from an adaptation of theories of mechanical manipulator control to biological arm control. The notion of an incomplete tabular representation of movement parameters (i.e., sparse lookup tables) is put forth to solve the problems of intractability of the equations of motion and of mechanical modeling inaccuracies. The implication of a sparse lookup table, namely that a relatively small number of movements can be executed accurately, will lead us to test experimentally: (1) for human arm movements that are executed less accurately than others, and (2) how a sparse lookup table can be used to generate more complex arm trajectories. Experiments with monkeys will reveal the extent to which feedback is required for proper execution of these strategies.